Merged

After the 2015.6.1 update, LR has developed an issue wherein after an extended period of being open (or possibly after my computer wakes from sleep), it either freezes completely and needs to be forced to quit or slows down to the point of being unusable. By that, I mean that inputs either from keyboard or mouse take between five and ten seconds to go through. Other programs are fine. Force-quitting and restarting LR gets rid of the problem.

Not sure the exact version it started, but I've been experiencing similar behavior since one of the most recent updates - 2015.6 or 2015.6.1.

Difference is, I'm on Windows 10 and Lr doesn't just become sluggish, it's completely unresponsive and has to be killed through Task Manager. To work around it, I just started closing Lr when I knew I'd be away from my computer for extended periods of time. Inconvenient, but not the end of the world for me.

You should update to LR 6.7, which is the latest version and just came out yesterday. LR 6.6.1 was a problem update and had severe issues, also with the import of pics and was fixed with 6.6.2. The 6.7 update has even more fixes, so that is the one to install.